Microbial keratitis is a serious eye infection that can lead to permanent vision loss through corneal scarring or perforation. Pseudomonas aeruginosa is one of the most frequent ocular isolates and has been shown to be associated with 75% of contact lens mediated infectious keratitis. Contact lens wearers are more prone to microbial keratitis and the development of new therapies is an important field of research. The current practice is to treat the infection with antibiotics, but the recent emergence of resistant bacterial strains has heightened the need for alternative treatments. Although the exact sequence of events leading to microbial keratitis has not been fully elucidated, the role of the host and microbial proteases in keratitis has been well documented. This application proposes the use of a novel "Protector protein" mediated technology as an alternative regimen for combating keratitis. "Protector proteins" are novel molecules that have two distinct classes of activities. The first obvious activity is protein stabilization via refolding while the second less obvious but equally impressive group of Protector proteins, belong to the class of protease inhibitors. Our hypothesis is that ECI characterized "Protector proteins"; alphaA-Crystallin, gammaD-Crystallin and the chimeric protein, pepstatin/leupeptin/alphaA-Crystallin will inhibit the proteolytic enzymes secreted by the host and the pathogen, thus serving as a good therapeutic agent against the management of microbial keratitis. The specific aims designed for phase I of SBIR grant, are based on this premise and will provide us with significant in vitro biochemical analysis leading way to more telling in vivo animal model studies. We envisage that attachment of these "Protector proteins" onto extended wear soft contact lenses would significantly reduce the incidence of microbial keratitis associated with contact lens wearers and could attract significant portion of this market. In summary, this application proposes the use of a novel "Protector protein" mediated technology as an alternative regimen for combating keratitis.